It's a trick he's used before but, just as it slayed the crowd used at the Golden Jubilee ten years ago, it did again on Monday when Prince Charles opened his post-concert encomium to Her Majesty the Queen with the word "Mummy".The general rule is that the posher you are, the longer you go on calling your parents by what are traditionally their (or rather your) childhood monickers. So it is only right and proper that the poshest man in the land should still be calling his mother "Mummy" at the grand old age of 63 – although there is a school of thought that says only "Mama" and "Papa" should be used at the top of the English class tree, which leaves us with the delightful proposition that the royal offspring drop into the demotic to address their parents as a hilarious family in-joke. Or, of course, it simply means that the secret belief of the English aristocracy is right and that the Windsors are indeed nothing but German arrivistes who will never really be able to get things right.

Most of us plebs stop using "Mummy" and "Daddy" in fairly early childhood. I was about six when I first tried out "Mum" and "Dad" – nobody else at school was still using the other and as I had enough bullyable features beyond my control, I had to minimise all those that I could. After a few half-hearted attempts to make me return to lisping childhood innocence ("Wrong time, wrong place, wrong income bracket," I pointed out), the new names stuck and my younger sister naturally followed suit.

But when Charles says "Mummy", it is endearing because for a brief moment it humanises both him and the Queen. He should do it more often. It is, after all, a lot harder to revolt against a cuddly mother and son than a remote, unsmiling monarch and successor. Next time, she should respond, "Aw, hello Chucky-egg!" and secure the royals' future for the next 18 generations.